A recent study published in Nature magazine found that human brain evolution would not have been possible without eating meat. The report stated that energy saved from less chewing and the calorie-rich, nutritious benefits of meat played a large role in the evolution of facial and dental sizes, speech production organs, locomotion, thermoregulation and perhaps the size of the human brain. According to the report, “Meat requires less masticatory force to chew per calorie than the sorts of generally tough plant foods available to early hominins.”
Another report, published in the academic journal Elementa, found that a vegan diet uses a far less sustainable agricultural land base than omnivorous diets. Meat production is able to utilize pasture land and crop land that vegetables and fruits are unable to use. While a vegan diet is less land intensive, reducing the amount of meat products does not necessarily free more land for cultivation.